/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.sql.parser.ddl;

import org.apache.calcite.sql.SqlIdentifier;
import org.apache.calcite.sql.SqlNode;
import org.apache.calcite.sql.SqlNodeList;
import org.apache.calcite.sql.SqlWriter;
import org.apache.calcite.sql.parser.SqlParserPos;
import org.apache.calcite.util.ImmutableNullableList;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;

import java.util.List;

/**
 * ALTER DDL to ADD or REPLACE columns for a table.
 */
public class SqlAddReplaceColumns extends SqlAlterTable {

	private final SqlNodeList newColumns;
	// Whether to replace all the existing columns. If false, new columns will be appended to the end of the schema.
	private final boolean replace;
	// properties that should be added to the table
	private final SqlNodeList properties;

	public SqlAddReplaceColumns(
			SqlParserPos pos,
			SqlIdentifier tableName,
			SqlNodeList newColumns,
			boolean replace,
			@Nullable SqlNodeList properties) {
		super(pos, tableName);
		this.newColumns = newColumns;
		this.replace = replace;
		this.properties = properties;
	}

	public SqlNodeList getNewColumns() {
		return newColumns;
	}

	public boolean isReplace() {
		return replace;
	}

	public SqlNodeList getProperties() {
		return properties;
	}

	@Nonnull
	@Override
	public List<SqlNode> getOperandList() {
		return ImmutableNullableList.of(tableIdentifier, partitionSpec, newColumns, properties);
	}

	@Override
	public void unparse(SqlWriter writer, int leftPrec, int rightPrec) {
		super.unparse(writer, leftPrec, rightPrec);
		if (replace) {
			writer.keyword("REPLACE");
		} else {
			writer.keyword("ADD");
		}
		writer.keyword("COLUMNS");
		SqlWriter.Frame frame = writer.startList(SqlWriter.FrameTypeEnum.create("sds"), "(", ")");
		for (SqlNode column : newColumns) {
			printIndent(writer);
			column.unparse(writer, leftPrec, rightPrec);
		}
		writer.newlineAndIndent();
		writer.endList(frame);
	}

	protected void printIndent(SqlWriter writer) {
		writer.sep(",", false);
		writer.newlineAndIndent();
		writer.print("  ");
	}
}
